Hello Guest it is March 29, 2024, 11:00:27 AM

Author Topic: 4th axis is slowing X, Y, and Z  (Read 9154 times)

0 Members and 1 Guest are viewing this topic.

Offline Haik

*
  •  71 71
  • MachUser
    • View Profile
4th axis is slowing X, Y, and Z
« on: July 05, 2007, 06:01:48 PM »
Hi Forum,

I need some help getting Feedrate speed out of my setup... when a gCode line with only "A" on it runs all is fine and "A" is as fast as "F" is set, but lines with "A" and another axis like "X" "Y" and/or "Z" the feedrate drops to around 1.2 IPM which is like sooo very slow!

My setup is:

-Mach3 w/ G100
-4th Axis Motor Tuning settings: Steps[500], Velocity[2500] yes it's cranked!, Acceleration[1000]
-Tangential control[OFF]
-Settings page Rotation Diameters: A[+0.0001]
-Settings page Axis Ihibits[OFF] for all 6 axis'
-General Config Angular Properties [CHECKED/on] for A, B,and C
-ToolPath Configuation Use diameter For Feedrate[CHECKED/on]

My snippet of gCode is:
f50000 (cranked and still slow on A w/XYorZ)
x0 y0 z0
z-.187 (moves fast)
y2 (moves fast)
y0 (moves fast)
x2 a90 (moves SLOW!!!)
z.2 (moves fast)
x-.5 y0 (moves fast)
z-.187 (moves fast)
x0 y0 a90 (moves SLOW!!!)
x2 a180 (moves SLOW!!!)
...etc........etc.......


Also to rule out software/firmware woes I've tried different versions of Mach3, different versions of Mach3 G100 Plugin, and different version of G100 Plugin Firmware... all perform with same problem persisting.

Any help is h-u-g-e-l-y appreciated!!!

-Haik
Re: 4th axis is slowing X, Y, and Z
« Reply #1 on: July 06, 2007, 06:07:47 AM »
For what I understood from the video:

Settings page Rotation Diameters: A[+0.0001

should be the diameter of the block being milled. Did you try with, say, 100 mm ?

Gianni

Offline Haik

*
  •  71 71
  • MachUser
    • View Profile
Re: 4th axis is slowing X, Y, and Z
« Reply #2 on: July 06, 2007, 01:41:54 PM »
Thanks for the reply!... Yes, I did try a diameter, my units are 'inches' and I tried a variety of diameters from .5"-20" all having no effect.  The .0001 diameter is supposed to Mach to use the 'Z' value for calculating rotational feedrate, but that had no effect either.

-Haik

Offline Chaoticone

*
  • *
  •  5,624 5,624
  • Precision Chaos
    • View Profile
Re: 4th axis is slowing X, Y, and Z
« Reply #3 on: July 07, 2007, 10:36:37 PM »
Hey Haik,
   Do you have your a axis steps per set to = 1degree or 1 rotation?

Brett
;D If you could see the things I have in my head, you would be laughing too. ;D

My guard dog is not what you need to worry about!

Offline Haik

*
  •  71 71
  • MachUser
    • View Profile
Re: 4th axis is slowing X, Y, and Z
« Reply #4 on: July 07, 2007, 11:00:02 PM »
This I don't know... where in Mach do I find/make this setting???

Offline Chaoticone

*
  • *
  •  5,624 5,624
  • Precision Chaos
    • View Profile
Re: 4th axis is slowing X, Y, and Z
« Reply #5 on: July 07, 2007, 11:33:31 PM »
It is in config, motor tuning, steps per. Did you do the math for one rotation or one degree?

Brett
;D If you could see the things I have in my head, you would be laughing too. ;D

My guard dog is not what you need to worry about!

Offline Haik

*
  •  71 71
  • MachUser
    • View Profile
Re: 4th axis is slowing X, Y, and Z
« Reply #6 on: July 07, 2007, 11:41:07 PM »
Well... It's set to 500 steps:  My turntable is geared at 90:1 and stepper pulleys are 1:1

The thing is I get 90 degrees of rotation when I do A90... I do think this area of my setup needs investigation.   How can I test both approaches or can I ???

Offline Chaoticone

*
  • *
  •  5,624 5,624
  • Precision Chaos
    • View Profile
Re: 4th axis is slowing X, Y, and Z
« Reply #7 on: July 07, 2007, 11:46:36 PM »
Haik,
   Are you single stepping, microstepping, servos? How many pulses does it take to make the motor turn 1 round?

Brett
;D If you could see the things I have in my head, you would be laughing too. ;D

My guard dog is not what you need to worry about!

Offline Haik

*
  •  71 71
  • MachUser
    • View Profile
Re: 4th axis is slowing X, Y, and Z
« Reply #8 on: July 08, 2007, 03:09:40 PM »
I'm using stepper motors and I have G203v (10 microstep) drivers on all axis, but on XY and Z the steps are set to 4000 steps and the screws are 2 TPI. So I'm "microstepping"  and there are 2000 step pulses per turn.

On A the steps are currently set to 500, so I believe I'm set to "steps per degree" (as in 500 steps p/deg, 4 deg p/crank rot, 1:1 pulleys, 90:1 table gearing, 180,000 steps for 360 deg). It seems that 180,000 steps p/360 degrees is radically high, maybe I should be full-stepping (div by 10) and then the step relationship between XYZ and A will be closer?

I hope this is the info your asking for... and "Thanks" for helping!!!
« Last Edit: July 08, 2007, 03:40:34 PM by hbaba »

Offline Chaoticone

*
  • *
  •  5,624 5,624
  • Precision Chaos
    • View Profile
Re: 4th axis is slowing X, Y, and Z
« Reply #9 on: July 08, 2007, 05:41:17 PM »
Yup, that is what I was wanting to know. :) I can't remember for sure but I'm certain I have seen this come up before. Can you try tuning your motor to Stepr per rev. and see how it does? It sounds like it is right as is though. Hmmmmmmmmm. Can you post your XML? I don't have a 4th axis but will look at it and see if I can find anything to cause this.

Brett
;D If you could see the things I have in my head, you would be laughing too. ;D

My guard dog is not what you need to worry about!